Closure plate for electrical panelboard



Oct. 11, 1966 M. J. GEORGE ETAL 3,278,066

CLOSURE PLATE FOR ELECTRICAL PANELBOARD Filed May 12, 1955 @wh @fw ya@ United States Patent O 3,278,066 CLOSURIE PLATE FOR ELECTRICAL PANELIBGARD Melvin J. George, Southfield, Mich., and Harris I. Stanback, Lexington, Ky., assigner-s to Square D Company,

Park Ridge, lll., a corporation of Michigan Fired May 12, 196s, ser. No. 455,270 Claims. (Cl. 220-24.3)

This invention relates to closure plates for the front trim panels or covers of electrical panelboards of the type into which circuit breakers or fusible units may be plugged. When a panelboard can accommodate more circuit breakers or fusible units than are presently needed, closure plates are installed on the trim panel to cover the unused spaces, the closure plates being removable when it is later desired to install additional circuit breakers or fusible units to accommodate additional circuits.

An object of the invention is to provide a simple, economical, and sturdy closure plate which, when installed in a trim panel, cannot be readily removed therefrom merely by pulling it from the front of the trim panel.

Another object is to provide a closure plate having means adjacent one end for forming a pivotal connection with an edge portion of an opening in a trim panel and means adjacent the other end for forming a snap-in connection with an opposite edge portion of the opening in the trim panel.

A further object is to provide a closure plate suitable for use in either of two types of trim panels, one of which has discriminating means and the other of which does not have discriminating means.

Other objects will become apparent when the following specification is considered `along with the accompanying drawings, in which:

FIG. 1 is a fragmentary front view of a trim panel having a closure plate constructed in accordance with the invention mounted thereon;

FIG. 2 is a perspective View of the closure plate of FIG. 1;

FIG. 3 is a sectional view taken along the line 3-3 of FIG. 1;

FIG. 4 is `a sectional view taken along the line 4-4 of FIG. 3;

FIG. 5 is a view similar to FIG. 1, but showing a modified trim panel on which the closure plate of FIGS. 1-4 is mountable;

FIG. 6 is a fragmentary sectional view taken along the line 6-6 of FIG. 5; and

FIG. 7 is a fragmentary sectional view of the closure plate -of FIG. 1 before installation.

With reference to the drawings, a closure plate 10 constructed in accordance with the invention includes a front portion 12, which may be embossed as shown, a pair of oppositely disposed, generally straight side flanges 13 and 14, and a pair of oppositely disposed, curved end flanges 15 and 16. The end flange 15 is provided with a slot 17 (FIG. 4), and a portion 18 on the opposite side of the slot 17 from the front portion 12 is twisted outwardly as shown in FIG. 3 to provide a Icamming surface 18a and a latching surface 18b. The end flange 15 is reversely curved, as at 20, for increased resiliency.

The end flange 16 is provided with a double reverse curvature, or S-curved cross sectional shape, as shown in FIG. 3, and may be provided with a slot 21 for a purpose hereinafter set forth.

FIG. 1 shows a portion of a trim panel 22 having an opening 23 therein. The opening 23 is partially defined by a pair of opposed parallel side edge portions 24 and 25 which are spaced apart sufficiently to receive the raised portions of the casings of fusible switches such as 3,278,066 Patented Get. 1l, 1966 indicated at A in FIG. 1 and disclosed in application, Serial No. 423,680, filed on January 6, 1965, and entitled, Cartridge Fuse Pull-Out Switch. To install a closure plate 10 on a trim panel 22, the end flange 16 thereof is first inserted over one of the edge portions 24 or 25, as shown in FIG. 3, forming, in effect, a pivotal connection therebetween. The closure plate is then swung down from the dotted-line position of FIG. 3 to snap the end flange 15 into latching engagement with the other edge portion. Once installed, the closure plate cannot be pulled off a trim panel unless the latching flange 15 is first bent tow-ard the end flange 16 from the inside of the trim panel to move the latching surface 18b out of interfering relationship with the edge portion of the trim panel.

FIG. 5 shows a portion of a modified trim panel 32 having an opening 33 therein. The opening 33 is partially defined by a pair of opposed parallel side edge portions 34 and 35. The edge portion 34 is straight, but the edge portion 35 is provided with a plurality of equally spaced inwardly projecting tongues 36. The larger distance between the edge portion 34 and the edge portion 35 at the base of the tongues 36 is the same as the distance between the edge portions 24 and 25 of the trim panel 22. The trim panel 32 is designed to reject fusible switches A such as disclosed in the aforementioned application, but to accommodate circuit breakers such as indicated at B in FIGS. 1 and 5 and disclosed in U.S. Patent No. 3,134,051, issued on May 19, 1964. The casings of such circuit breakers B each have a raised portion, to be received in `a trim panel, which is shorter or narrower than the raised portion of a casing of a fusible switch A such as disclosed in the aforementioned application. The distance between the edge portion 34 and the free end of a tongue 36 is suflicient to accommodate the raised portion of a casing of such a circuit breaker B, but insutlicient to accommodate the raised portion of a casing of such a fusible switch A.

When the end flange 16 is provided with the slot 21, the closure plate 10 may be used on either of the trim panels 22 and 32. When a closure plate 10 is installed on the trim panel 32, the slot 21 in the end flange 16 accommodates the respective tongue 36, as shown in FIG. 6.

It will be seen that we have provided a closure plate which may be used on either of two types of trim panels, one of which has discriminating means such as tongues 36 and the other of which has no such discriminating means. Further, when the closure plate is installed on a trim panel, it cannot be removed unless the latching flange 15 on the inside of the trim panel is bent inwardly.

The trim panels 22 and 32 are preferably made of steel, and the trim panel 22 is thicker than the trim panel 32. The distance between the reversely curved portion 20 and the latching surface 18b of a closure plate 10 is sullicient to accommodate the thicker trim panel 22. To prevent looseness when a closure plate 10 is installed on the thinner trim panel 32, the end of the closure plate 10 having the end flange 15 is biased outwardly to maintain the latching surface 18h in engagement with the inner surface of the trim panel 32. The biasing force is supplied by resilient deformation of the end flange 16. FIG. 7 shows the shape of the end flange 16 before installation, it being noted that the free end portion thereof extends at an angle to the front portion 12 of the closure plate. When the closure plate is installed on the thicker trim panel 22, the end flange 16 is resiliently deformed so that the free end portion thereof extends substantially parallel to the front portion 12 of the closure plate. When the closure plate is installed on the thinner trim panel 32, the end flange 16 is resiliently deformed to a lesser extent than when it is installed on the thicker trim panel 22, but it is nevertheless still deformed sufficiently to exert an outward force on the other end of the closure plate.

Various modifications may be made in the structure shown and described without departing from the spirit and scope of the invention.

We claim:

1. For use with a trim panel of an electrical panelboard, said trim panel having an opening therein partially dened by va pair of oppositely disposed, spaced, parallel edge portions, a closure plate for partially closing said opening, said closure plate comprising an elongated plate member having a pair of oppositely disposed end anges, one of said end anges having means cooperable with one of said edge portions of said trim panel to form a pivotal connection therebetween and having an outwardly extending free end portion adapted to underlie said one edge portion of said trim panel when said closure plate is in place on said trim panel, and the other of said end anges forming a resilient latching means co operable with the other of said edge portions of said trim panel to maintain said closure plate in place on said trim panel, said other end flange including la camming surface engageable with said other edge portion of said trim panel as said closure plate is pivoted about said one edge portion of said trim panel thereby to resiliently bend said other end flange inwardly as said camming surface moves past said other edge portion of said trim panel, and a latching surface engageable with the inner surface of said other edge portion of said trim panel upon completion of the movement of said camming surface past said other edge portion of said trim panel and the bending of said other end ange back outwardly toward its original unbent position.

2. A closure plate as claimed in claim 1, wherein said one end flange has a generally S-curved cross sectional shape.

3. A closure plate as claimed in claim 1, wherein said other end flange is reversely curved for increased resiliency.

4. For use with a trim panel of an electrical panelboard, said trim panel having an opening therein partially defined by a pair of oppositely disposed, spaced, generally parallel edge portions, one of said edge portions having a tongue portion projecting inwardly toward the other of said edge portions, a closure plate ias claimed in claim 1, wherein said one end flange is provided with a slot for receiving said tongue portion.

5. A closure plate as `claimed in Iclaim 1, wherein said one end flange is so shaped as to be resiliently deformed by engagement of said outwardly extending free end portion with the inner surface of said one edge portion of said trim panel When said closure plate is in place on said trim panel to thereby bias said latching surface of said other end flange against said inner surface of said other edge portion of said trim panel.

No references cited.

THERON E. CONDON, Primary Examinez'.

I. B. MARBERT, Assistant Examiner. 

1. FOR USE WITH A TRIM PANEL OF AN ELECTRICAL PANELBOARD, SAID TRIM PANEL HAVING AN OPENING THEREIN PARTIALLY DEFINED BY A PAIR OF OPPOSITELY DISPOSED, SPACED, PARALLEL EDGE PORTIONS, A CLOSURE PLATE FOR PARTIALLY CLOSING SAID OPENING, SAID CLOSURE PLATE COMPRISING AN ELONGATED PLATE MEMBER HAVING A PAIR OF OPPOSITELY DISPOSED END FLANGES, ONE OF SAID END FLANGES HVING MEANS COOPERABLE WITH ONE OF SAID EDGE PORTIONS OF SAID TRIM PANEL TO FORM A PIVOTAL CONNECTION THEREBETWEEN AND HAVING AN OUTWARDLY EXTENDING FREE END PORTION ADAPTED TO UNDERLIE SAID ONE EDGE PORTION OF SAID TRIM PANEL WHEN SAID CLOSURE PLATE IS IN PLACE ON SAID TRIM PANEL, AND THE OTHER OF SAID END FLANGES FORMING A RESILIENT LATCHING MEANS COOPERABLE WITH THE OTHER OF SAID EDGE PORTIONS OF SAID TRIM PANEL TO MAINTAIN SAID CLOSURE PLATE IN PLACE ON SAID TRIM PANEL, SAID OTHER END FLANGE INCLUDING A CAMMING SURFACE ENGAGEABLE WITH SAID OTHER EDGE PORTION OF SAID TRIM PANEL AS SAID CLOSURE PLATE IS PIVOTED ABOUT SAID ONE EDGE PORTION OF SAID TRIM PANEL THEREBY TO RESILIENTLY BEND SAID 